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LETTERS TO THE EDITOR
8. Kersten JR, Schmeling TJ, Orth KG, et al: Acute hyperglycemia abolishes ischemic preconditioning in vivo. Am J Physiol Heart Circ Physiol 275:H721-H725, 1998 9. Kersten JR, Toller WG, Pagel PS, Warltier DC: Diabetes and acute hyperglycemia abolish mitochondrial KATP channel-induced cardioprotection in vivo. Anesthesiology 93:A680, 2000 10. Cleveland JC, Meldrum DR, Cain BS, et al: Oral sulfonylurea hypoglycemic agents prevent ischemic preconditioning in human myocardium: Two paradoxes revisited. Circulation 96:29-32, 1997 11. Baines CP, Wang L, Cohen MV, Downey JM: Myocardial protection by insulin is dependent on phosphatidylinositol 3-kinase but not protein kinase C or KATP channels in the isolated rabbit heart. Basic Res Cardiol 94:188-198, 1999 12. Lazar HL, Philippides G, Fitzgerald C, et al: Glucose-insulin-potassium solutions enhance recovery after urgent coronary artery bypass grafting. J Thorac Cardiovasc Surg 113:354-362, 1997 13. Heng MK, Norris RM, Singh BN, Barratt-Boyes C: Effects of glucose and glucose-insulin-potassium on haemodynamics and enzyme release after acute myocardial infarction. Br Heart J 39:748-757, 1977 14. Wildenthal K, Mierzwiak DS, Mitchell JH: Acute effects of increased serum osmolality on left ventricular performance. Am J Physiol 216:898-904, 1969 15. Grundy SM, Benjamin IJ, Burke GL, et al: Diabetes and cardiovascular disease: A statement for healthcare professionals from the American Heart Association. Circulation 100:1134-1146, 1999 16. American Diabetes Association, National Heart, Lung, and Blood Institute, Juvenile Diabetes Foundation International, National Institute of Diabetes and Digestive and Kidney Diseases, and the American Heart Association: Diabetes mellitus: A major risk factor for cardiovascular disease. A Joint Editorial Statement. Circulation 100:1132-1133, 1999 doi: 10.1053/jcan.2001.23343
Management of Complex Defects With Pulmonary Hypertension To the Editor: I congratulate Drs. Filipovic et al1 for successful management of a patient with atrioventricular septal defect and severe pulmonary hypertension undergoing major orthopedic surgery. I would like to make the following comments on the case report: (1) The authors said, “Transthoracic echocardiography showed a large right ventricle and a smaller left ventricle with bidirectional shunt through the atrioventricular septal defect. Echocardiography revealed a patent ductus arteriosus with bidirectional shunting.” It is not clear if the patent ductus arteriosus was an associated finding that was missed on the transthoracic echocardiogram. (2) The use of a pulmonary artery catheter in the perioperative period is highly justifiable in this case for accurate monitoring of changes in the pulmonary artery pressure (PAP) during the anesthetic and recovery period. (3) It is common in this center to see patients with atrial septal defect or ventricular septal defect with bidirectional shunting presenting for definitive surgery. We have developed the following strategy to offer them a safe option. The atrial septal defect or ventricular septal defect is closed with a fenestrated Dacron patch under conventional cardiopulmonary bypass. The PAP is monitored closely for the next 6 months, and the fenestration in the patch is occluded with a device in the catheterization laboratory if the PAP has regressed by that time. This strategy cannot be applied to the present case, however, in view of the nature of the defect and associated Down’s Syndrome. K. Muralidhar, MD Department of Anaesthesia Manipal Heart Foundation Bangalore, India REFERENCE 1. Filipovic M, Seeberger MD, Bolz D, Frei F: Management of a patient with an atrioventricular septal defect and severe pulmonary hypertension undergoing major orthopedic surgery. J Cardiothorac Vasc Anesth 14:584-585, 2000 doi: 10.1053/jcan.2001.23343
Response To the Editor: We appreciate the interest of Dr. Muralidhar in our article,1 and we would like to comment on his questions and suggestions as follows: (1) The patent ductus arteriosus with bidirectional shunting was seen in the transthoracic echocardiographic examination. (2) We agree with Dr. Muralidhar that the use of a pulmonary artery catheter would have been a viable option in our patient. To our knowledge, there are no published studies on the respective advantages of transesophageal echocardiography (TEE) and pulmonary artery catheterization in such patients. If the anesthesiologist in charge is not experienced with TEE, the use of a pulmonary artery catheter might be more advisable, despite the following limitations: Measurements of cardiac output are unreliable